Pumping device



9 F. G. SCHWEISTHAL. 399829966 PUMPING DEVICE Filed Feb. 2 7

2 Sheets-s l Patented Dec. 4, 1934 UNITED STATES PATENT} OFFICE Ste corporation of Virginia Application February 20,

7 Claims.

This invention relates to improvements in a combined fuel pump and vacuum booster and more particularly to improvements in the design of the vacuum booster pumping device.

It has been proposed to combine a fuel pump and a vacuum pump booster in one unit for combined operation from a single engine-actuated lever, and one arrangement has been to support the pumping members of both the fuel pump and the vacuum pump in horizontal positions and on the upper and lower sides respectively of the actuating lever, whereby the fuel pumping chamber is on the upper side of the upper pumping member and the vacuum pumping chamber is on the lower side of the lower pumping member.

It is an object of the present invention to disclose improvements in the design of the operating parts and the relative position of the i parts with respect to each other in the pump casing in order to obtain a compact arrangement and a smooth and quiet operation of both pumps.

It is a feature of the present improvements 5 that the capacity of the vacuum pump chamber may be reduced to a minimum since the resilient means for producing the suction stroke of the vacuum pump is positioned outside of the pumping chamber. It is also a feature that. the resilient means, which may comprise a pair of springs, are positioned in pockets separated from direct communication with the lever-receiving cavity of the casing, whereby the spring pockets do not collect oil and water, which may cause trouble from freezing.

Various other detail improvements and advantages of design will be more readily apparent from the following description taken in connection with the attached drawings, in which 40 Figure 1 is a sideelevation of the combined pumping device;

Figure 2 is a plan view thereof;

Figure 3 is a partial vertical section take on the plane indicated 33 in Figure 2;

Figure 4 is a bottom view of a portion of the device;

Figure 5 is a vertical section taken on the plane indicated 5-5 in Figure 3;

Figure 6 is a detail section taken on the plane indicated 6-6 in Figure 4;

Figure 7 is a similar detail section taken on the plane indicated 77 in Figure 4;

Figure 8 is a section similar to Figure 3 show- 55 h s a modified construction, and

wart-Warner Corporation,

Chicago, 111., a

1932, Serial No. 594,219

Figure 9 is a vertical section taken on the plane indicated 9-9 in Figure 8.

The casing includes a central part 10, a top head 12 and a bottom head 14. The design of the head 12 which forms a cover for the fuel pump may be similar to that disclosed in my application, Serial No. 582,226, filed December 14, 1931, and includes a lateral extension 16 provided with an inlet connection 18 and having secured to its underside a transparent fuel receiving bowl 20. The head 12 also includes a vapor dome 22 and an outlet connection 24. The head 12 is recessed on its underside to form a fuel pumping chamber 26. A flexible pumping diaphragm 28, having clamped to the upper and lower sides of its central area, strengthening disk members 30 and 32, forms a movable wall of the pumping chamber 26. The marginal edge 34 of the diaphragm is clamped between the head 12 and the central casing part 10 by means of screw bolts 36.

The casing part 10 is recessed on its upper side to form a cavity 38 for receiving a spring 40 which surrounds a cylindrical projection 42. The spring 40 seats at its lower end upon the bottom wall of the cavity 38 and reacts upwardly against the diaphragm 28 through a cup-shaped disk 32 which positions the upper end of the spring. The expansion of spring 40 produces the discharge stroke of the diaphragm s5 28. For moving the diaphragm for its suction stroke a stem member 46 is secured at its upper end to the diaphragm by a nut 48. The stem member 46 is a stamped metal piece bent at its lower end to form a box-shaped abutment seat 50 and receives the arm 52 of lever 54. Lever 54 is carried by pivot 56 and is positioned trans versely of the cavity 58 in the casing part 10 by stamped clip 60.

The casing part 10 has a flange 62 for mounting the entire unit upon an engine casing adjacent an aperture thereof with the cavity 58 in communication with the interior of the engine casing and the lever arm 64 protrudes into the engine casing for thrust engagement with a rotatable cam 66. The lever arm 64 is maintained in thrust engagement with the cam 66 by spring 68 received within a spring cavity '70 formed in the casing part 10 and reacting downwardly upon the up-turned lug 72 of the stamped clip 60.

When the lever 54 is moved for its positive stroke by rotation of the cam 66, the inner arm 52 will move downwardly whereby the contact portion 74 of lever arm 52 will engage the abut- 11 ment of stem 46 and transmit a positive suction stroke to the pumping diaphragm 28. Upon retractive movement of the lever 54, the arm 52 will disengage from the stem 46 and permit the pumping member to move for its discharge stroke in accordance with the expansion of spring 40. The construction as thus far described is substantially similar to the fuel pump design shown in my above-noted application.

The casing part is recessed on its underside to form a chamber 76 which is placed in communication with the cavity 58 through a vertical passage 78 and a transverse opening 80 at the upper portion of the cavity 58. The chamber '76 is closed on its underside by a flexible vacuum pump diaphragm 82 which has secured to its upper side a disk 84 and having secured to its lower side a disk 86. The disk members 84 and 86 are secured to the diaphragm 82 by rivet 88 which also serves to clamp to the upper side of the diaphragm a cup-shaped member 90 positioning an annular cushion abutment 92, the marginal edge 94 of the diaphragm 82 is clamped to the underside of the casing part 10 by the bottom head member 14 which is secured by screw bolts 96. The pumping chamber 98 between the inner surface of the head 14 and the diaphragm 82 is of relatively small capacity. It will be noted that the disk 86 on 0 the lower side of the diaphragm has a beaded edge 100 formed to take up the slack in the "diaphragm 82 and the head 14 has an annular ridge 102 adapted to fit within the groove of the beaded edge 100. The head member 14 has an inlet connection 104 adapted to be connected to. the vacuum chamber of a vacuum-operated device, such as a windshield wiper. The outlet connection 106 of the head member 14 is adapted to lead to the intake manifold of the engine. The inlet passage 108 through the head member 14 is controlled by an inlet check valve 110 adapted. to seat on valve seat member 112 and normally urged to its seat by a leaf spring 114 secured at one end by pin 116. It will be noted that the inlet check valve may be assembled from the upper side of the head 14. The outlet passageway 118 is controlled by'the outlet check valve 120 normally urged to seated position upon valve seat member 122 by a leaf spring 124 secured at one end by pin 126. The head 14 has a relatively large opening on its underside to permit the assembly of the outlet check valve and this opening is closed by a stamped 5 cap 128. The passageways and check valves are included in a substantially tubular enlargement 130 on the underside of the head member, as clearly shown in Figure 4.

The casing part 10 has a pair of vertical spring 0 receiving pockets 132 extending downward from the spring cavity 38 and the pockets 132 are adapted to receive compression springs 134 which seat at their lower end upon the bottom walls of the pockets 132. The springs react at their upper ends against cap members 136 secured to the upper ends of the arms 138 of a U-shaped member 140. The arms 138 extend through openings 142 at the bottoms of pockets 132. The lower portion of the member 140 forms a disk 144 which is secured to the upper side of the diaphragm 82 by the rivet 88. The expansion of springs 134 moves the diaphragm 82 in an upward direction for its suction stroke.

The casing part 10 has an opening 146 between 7 the cavity 58 and the cavity '76 which receives the reciprocable sleeve 148 including a collar portion 150 at its upper end for engagement by the yoke-shaped end 152 of the lever 54. The sleeve 148 is guided for vertical reciprocation by a fixed pin 154 secured by its reduced upper end 156 to the casing wall 158 between the spring cavity 38 and the lever receiving cavity 58. The sleeve 148 has a lost motion engagement at 160 with the cushion abutment 92 whereby movement of the sleeve 148' in a downward direction through positive movement of the lever 54 will move the diaphragm 82 for its discharge stroke and retractive movement of the lever will move the sleeve 148 away from the diaphragm 82 and permit the suction stroke of the diaphragm 82 through expansion of the springs 134. The function of the vacuum pump as a booster will be readily understood since, so long as the intake manifold suction is sufllcient, the vacuum pump will be held out of operation but when the intake manifold suction becomes'insuflicient, the vacuum pump begins to operate to maintain the desired degree of suction.

Figures 8 and 9 illustrate a modified arrangement in which the diaphragm 82 is replaced by the cup-shaped leather piston 162 clamped between a disk 164 on its upper side and a disk 166 on its underside. The annular flange of the leather piston 162 curves upwardly against the cylindrical wall 168 of the casing part 10 for sealing the pumping chamber at the underside of the piston. The construction is otherwise substantially identical with that disclosed in the previous design.

It will be noted that the spring pockets 132 are not in direct communication with the lever receiving cavity 58 and therefore do not collect oil from the engine casing.

I claim:

1. In a pumping device, a casing having an expansible and reducible pumping chamber therein, a reciprocable pumping member forming a movable wall of said pumping chamber, resilient means for moving said pumping member in a direction to enlarge said pumping chamber, a guide pin fixedly supported by said casing concentric with the axis of said pumping member, a reciprocable sleeve slidable on said guide pin, a lever pivotally supported by said casing having. an arm in operative engagement with the sleeve, said sleeve being adapted to engage the pumping member on the side opposite the pumping chamber for moving said pumping member in a direction opposed to the resistance of said resilient means.

2. In a pumping device, a casing having an expansiblel and reducible pumping chamber therein, a reciprocable pumping member forming a movable wall of said pumping chamber, resilient means positioned outside of said pumping chamber and operative to move the pumping member in a direction to enlarge the pumping chamber, a cushion abutment secured to said pumping member on the side opposite the pumping chamber, a guide pin fixedly supported by said casing concentric with the axis of said pumping member, .a reciprocable sleeve slidable on said guide pin and a lever pivotally supported by said casing for moving said sleeve, said sleeve being adapted to contact at one end with said cushion abutment to move said pumping member ina direction opposed to the resistance of said resilient means. 1

3. In a pumping device, a casing having an expansible and reducible pumping chamber therein, a reciprocable pumping member forming a movable wall of said pumping member, a guide pin fixedly secured to said casing concentrio with the axis of said pumping member, aconstant stroke reciprocable sleeve guided for movement by said guide pin and adapted to engage said pumping member by thrust contact at one end of said sleeve, a pair of compression springs arranged on opposite sides of said sleeve and parallel thereto, said springs being adapted. to react at their ends towards the pumping member upon the casing and means secured to said pumping member receiving the reaction from the other ends of said springs whereby said pumping member is normally maintained in thrust engagement with said reciprocable sleeve.

4. In a pumping device, a pump casing adapted to be supported on an engine casing for operation from an engine-driven cam within said engine casing, said casing having a cavity extending thereinto from communication with said engine casing, a lever pivotally supported within said casing cavity, a guide pin fixedly secured within said casing cavity to the top wall of said cavity, a sleeve reciprocable upon said guide pin, said lever having a yoke-shaped end for engaging said sleeve to transmit movement thereto in either direction, a reciprocable pumping diaphragm positioned on the underside of said casing, ahead member having inlet and outlet connections and recessed on its underside to form a pumping chamber, said head member being secured to the underside of said casing and clamping the marginal edge of said pumping diaphragm, a lost motion contact member on the side of said diaphragm opposite to the pumping chamber, said sleeve being adapted to engage said lost motion contact member in one direction of movement and resilient means for moving said diaphragm in a direction opposite to the movement produced by the reciprocation of said sleeve whereby said contact member is normally held in engagement with said sleeve.

5. In a vacuum booster, a casing adapted to be mounted on an engine casing, said casing having a cavity in communication with the interior of said engine casing, a lever pivotally supported by said casing and having an arm extending into said casing cavity, an expansible and reducible pumping chamber within said casing at the bottom side thereof, an inlet connection to said pumping chamber from a chamber within which a vacuous condition is to be produced, an outlet connection from said pumping chamber to the intake manifold of the engine, a reciprocable pumping member forming the upper movable wall of said pumping chamber, said casing having vertically disposed spring-receiving pockets separated from direct communication with said casing cavity by vertical walls of said casing, compression springs in said spring pocke s for transmitting suction movement to said diaphragm, a reciprocable operating member guided for vertical movement by said casing and extending into said casing cavity for engagement with said lever arm and said reciprocable member being adapted to engage said pumping member by thrust contact in a downward direction to transmit positive discharge movement to said pumping member against the resistance of said springs.

6. In a pumping device, a casing having a pumping chamber therein, a pumping member cooperating with said pumping chamber, a U- shaped member attached intermediate its ends to said pumping member, a pair of springs reacting between said casing and the ends of said U-shaped member to move said pumping member in one direction and means for moving said pumping member in the opposite direction against the resistance of said springs.

7. In a pumping device, a casing having a pumping chamber therein, a reciprocable pumping member cooperating with said pumping chamber, resilient means for moving said pumping member in a direction to enlarge said pumping chamber, a stem positioned by said casing concentric with the axis of said pumping member, a spool-shaped member reciprocable on said stem and adapted to transmit movement to said pumping member against the resistance of said resilient means by thrust engagement therewith and a cam actuated lever pivotally supported by said casing having a yoke-shaped end in operative engagement with said spool-shaped member.

FRED G. SCHWEISTHnL. '125 

